Saturday, June 26, 2010

Kickin' it old school

I've never really understood what that meant. Kicking what, precisely? And what does 'old school' mean? Is it like "way back when," before the focus of our schools was almost completely centered on teaching to the government-mandated competency tests? Well, it's probably another of those phrases that make no sense if one takes them literally. You know, like "temporary tax" or "can we still be friends?" Life has a way of teaching you how to read between the lines when it comes to things like that.

Back in the early 70's when Van's Aircraft was comprised of one guy and one single-seat airplane (the RV-3), building a kit airplane was nothing like it is now. By "kit" the manufacturer typically meant a box of raw materials, a set of plans, and a few pages of notes about how to put it all together. The raw materials were somewhat more advanced than a few boxes of bauxite ore from which you would smelt and shape your own aluminum sheets, but not by much. Even so, the fact that parts like wing ribs and the like were pre-formed was orders of magnitude better than the previous standard: the "plans built" plane. Those truly were old school. You would have to form every single piece from raw stock. By way of contrast, it is relatively rare while building the RV-12 to even have to drill your own holes.

Every now and then, though, we come across a part that we get to "fabricate" on our own. A case in point:

This is one of the situations where we start from raw, off-the-shelf material.

The fact that there were 70 inches of material remaining gave me pause, but for I set the disturbing thought that there are going to be many, many more parts to fabricate aside and concentrated on the two-inch job at hand. It was very straightforward: measure, mark, and cut.

This part is a brace that will help support the weight of the gascolator.

A Gascolator, also known as a main line strainer, sediment bowl or fuel strainer acts primarily as a fuel drain for water and small particles of sediment and is usually found at the lowest point of an aircraft's fuel system. The gascolator is located below the level of the aircraft's carburetor and fuel tanks and on light aircraft is commonly located on the front of the firewall, as low as possible.

Once formed, it needs to be drilled to support a nutplate. This is done by match drilling through holes already drilled into the firewall by Van's. The brace needs to be held in place while drilling through it, and this is apparently a recipe for drilling into your own (or, preferably, a helper's) fingers. As such, the instructions suggest holding the brace in place with a small wooden block. This is exactly the kind of thing "old school" builders would have had to learn on their own. Once learned, though, I have to think that this is a lesson that would only need to be learned once! If not, I would respectfully suggest that such a slow-witted builder might not be the best candidate for building and flying an airplane. A nice set of Adirondack chairs might be a better idea. Padded, preferably.

Once the rivet holes for the nutplate are drilled, the brace can be held in place with clecos. Then it becomes easier to drill the two holes that will be used to rivet the brace to the side of the tunnel.

This raw stock is not alclad, so it has no inherent corrosion protection. It gets primered before final installation.

Do those two rivets look like they're centered on the flange? No. No they don't. That is why I'm not building an RV-3. I like the new school!

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